15 years ago I had a job where I'd be talking to my teammates about our tech infrastructure or our databases and then one of them would respond with "that's what she said". And then the rest of the team (all men) would laugh, and everyone would forget what I just said, because it had become a sex joke.
It happened a lot. Luckily I was only there a year.
The result of this is that I haven't found "that's what she said" funny since 2009. If it's used in response to something I say nowadays, I just leave. Because it's being used to discredit and belittle me, even if the person pretends it isn't.
Lately I've been hearing people (men) use it more and more, and I don't know if it's the people I'm talking to or a shift in culture. Either way, I don't like it, even if it's not directed at me or another woman.
I ask that anyone who enjoys that phrase consider how they're using it, and see if they can come up with something similarly crude but non-gendered. Punch up.